The battle over dioxin contamination in this economically stressed region had been raging for years when a top Bush administration official turned up the pressure on Dow Chemical to clean it up.

On Thursday, following months of internal bickering over Mary Gade's interactions with Dow, the administration forced her to quit as head of the U.S. Environmental Protection Agency's Midwest office, based in Chicago.

Gade told the Tribune she resigned after two aides to national EPA administrator Stephen Johnson took away her powers as regional administrator and told her to quit or be fired by June 1